Currently, there are many known ways to treat long bone fractures. Common fracture treatments include: (1) nonsurgical immobilization; (2) osteosuture and tension band technologies; (3) percutaneous fixation (e.g., using pins, wires, screws etc.); (4) rigid intramedullary nailing (e.g., using a large rod and external screws); (5) flexible plate osteosynthesis (e.g., a “load sharing” suture); (6) arthroplasty (e.g., using a prosthesis); (7) plating and other indication specific techniques. Severe fractures that meet certain clinical criteria may require surgical repair rather than non-surgical immobilization.
The midshaft of an elongated or long bone is typically classified as the diaphysis.
In general, fracture fixation may provide longitudinal (along the long axis of the bone), transverse (across the long axis of the bone), and rotational (about the long axis of the bone) stability. Fracture fixation may also preserve normal biologic and healing function.
There are two primary categories for surgical fixation: a device that is within the skin (internal fixation); and a device that extends out of the skin (external fixation). There are two common types of internal fixation approaches for long bone surgery (a) a plate that is screwed to the outside of the bone; or (b) a rod that goes down the center of the bone.
Plates are characterized by relatively invasive surgery, support of fractured bone segments from one side outside of bone, and screws that anchor into the plate and through the entire bone. Successful repair is dependent on fracture pattern, bone quality, and patient tolerance of a foreign body, among other factors. Plates may not properly address the alignment and stability requirements for periarticular and intrarticular fractures.
Intramedullary rods or nails, such as those used in mid shaft treatments, are often used instead of plates and screws to reduce soft-tissue trauma and complications. Typically, an intramedullary rod or nail is fixed in diameter and is introduced into the medullary canal through an incision in the articular surface.
Flexible intramedullary rod-like solutions utilize structures that can be flexed for insertion into the medullary cavity through a diaphyseal or metaphyseal access site. The structures may then be made rigid inside the intramedullary cavity. The structures are often reinforced with polymers or cements. Making the structures rigid is important for surgical fixation.
It would be desirable, therefore, to provide apparatus and methods for bone fracture alignment and stabilization.